package com.chalenge;

import java.util.Scanner;  

public class KuoHao2 {  
  
    public static void main(String[] args) {  
  
	Scanner scanner = new Scanner(System.in);  
	int n = scanner.nextInt();  
	scanner.close();  
	if (n == 0) {
		System.out.println(0);
	}else{
		  System.out.println((int) (jiecheng(2 * n) / (jiecheng(n) * jiecheng(n) * (n + 1))));  
	}
      
    }  
  
    private static long jiecheng(int n) {  
	long result = 1;  
	for (int i = 1; i <= n; i++) {  
	    result *= i;  
	}  
	return result;  
    }  
}